George Osborne and his Labour shadow, Ed Balls, are on a list of those attending this week’s UK summit of the secretive Bilderberg group alongside the heads of Amazon and Google, both of which are under unprecedented political pressure over their companies’ aggressive tax avoidance policies.

Jeff Bezos, Amazon’s founder and chief executive, and Google’s executive chairman, Eric Schmidt, will rub shoulders with dozens of other figures from the global political and financial elite at the annual four-day meeting of the organisation, this year held near Watford. The group’s lack of transparency has long caused critics to characterise it as a secretive cabal.

A list of about 140 participants[2], made up almost overwhelmingly of white males but described as “a diverse group of political leaders and experts from industry”, was published on Monday by the organisation. It included only 14 women. The organisation said that those attending the summit at the Grove hotel would discuss topics including “jobs, entitlement and debt”, “how big data is changing almost everything” and “can the US and Europe grow faster and create jobs?”

“Thanks to the private nature of the conference, the participants are not bound by the conventions of office or by pre-agreed positions. As such, they can take time to listen, reflect and gather insights. There is no detailed agenda, no resolutions are proposed, no votes are taken, and no policy statements are issued.”

Attenders from financial backgrounds include Marcus Agius, the former chairman of Barclays who quit the post in the wake of the Libor interbank lending rate scandal, as well as Douglas J Flint, group chairman of HSBC Holdings plc, which was hit with a $1.9bn (£1.25bn) fine last December over allegations it had acted as banker for rogue states, terrorists and drug lords.

Peter Sutherland, the chairman of Goldman Sachs International, and Michael J Evans, vice-chairman of Goldman Sachs & Co, are the participants from the investment banking giant whose involvement in the sale of high-risk mortgage related investments has borne much of the blame for causing the 2008 global financial crisis.

As well as Balls and Osborne, other Britons attending include the Tory MP and minister Ken Clarke, and the former Labour MP and minister Peter Mandelson, who is listed as attending in his capacity as chairman of his strategic advice consultancy, Global Counsel, and as chairman of Lazard International, an investment bank.

This year’s meeting of the group, which first met 1954 with the aim of shoring up US-European relations in the cold war years, will attract scrutiny from the media along with, as usual, a small army of individuals harbouring a range of theories about what is really discussed behind the event’s closed doors. This year’s summit coincides in the UK with the outbreak of a fresh scandal over lobbying and calls for a statutory register of lobbyists.

A small number of journalists have received precious invitations to go behind the curtain. This year they include Martin Wolff of the Financial Times, the newspaper’s chief economics commentator, John Micklethwait, editor-in-chief of the Economist, as well as a number of others including Lilli Gruber, an anchorwoman at the privately owned Italian television channel, La 7 TV, Aslı Aydıntaşbaş, a columnist at Turkey’s Milliyet newspaper

Veteran participants include Henry Kissinger, the former US secretary of state, and Lord Carrington, the former Conservative politician and foreign secretary.